Automatic circuit-breaker.



A E. GREENE.

AUTOMATIC CIRCUIT BREAKER. I E APPLICATION FILED JUNE12,1905. v t986,708. Patented Mar. 14, 1911. j

3 SHEETS-SHEET 1.

( 41042286: fill/621607:

A. E. GREENE.

- AUTOMATIC CIRCUIT BREAKER.

APPLICATION FILED JUNE 12,1905.

Patented Mar. 14, 1911.

3 SHEETS-SHEET f? M8868! A; v m" 423501: v ream;

A. E. GEEENE.

AUTOMATIC CIRCUIT BREAKER.

APPLICATION FILED JUNE 12, 1995.

986,708. Patented Mar. 14, 1911.

3 SHEBTSSHEET 3.

. automatically UNITED STATES PATENT OFFICE.

AUSTIN E. GREENE, OF SOUTH BOSTON, MASSACHUSETTS, ASSIGFIOR TO SEARS B.CONDI'I, TB... OF BOSTON, MASSACHUSETTS.

auroua'rxc cxncurr-nnnaxnn To all whom it may concern:

Be it known that I, AUsTIN E. GREENE, a citizen of the United States,residing at SOuth'BoStom in the county of Suffolk and State ofMassachusetts, have invented an Improvement in Automatic Oircuit+Breakers, of which the following description, in connection with theaccompanying drawings, is, aspecification, like letters on the drawingsrepresenting like parts.

My invention is a circuit breaker provided with a single magneticcontrol responsive to 'an overload, and underload for releasing andtripping the circuitbrea'ker: l

In connection with motor generators, battery charging equipments, andwith enerators which are liable to be reversed, it is desirable to havea circuit breaker responsive either to an excessive amount of current orto a reduced amount of current. It is also desirable to have a circuitbreaker which is As herein shown,.I have accomplished the desired resultby providing a series coil and trip .11). connection with an easilytripped,

free-acting circuit breaker, said coil havinga double core, one part ofsaid core being" magnetized to retain the latch inlockin positionagainst the action of a counterba anci'ng force, so. that, upon theoccurrence of an underload, the trip is automatically released by theaction of said counterbalancing force, the other part of said core beingenergized to overcome the restraining influence of the first mentionedpart of said core upon the occurrence of an overload. I

In the accompanying drawings I have shown several embodiments 'of myinvention, each of which has advantages over the particular locationsand condip 3 engaged by a non-magnetic latch 25.

others for tions. Figure 1 shows one embodiment of my invention, partlyin section and largely in side elevation; Fig. 21is a fragmentarycross-sec- Specification of Letters iatent. V Patented Mar. 14, 1911.Application filed June 12,

1005. Serial No. acacia;-

tional detail thereof taken approximately on the line 2, Fig. 1; Fig. 3is an enlarged cross section of the armature and latch; Fig. 4 is a topplan view of armature with the latch removed; Fig. 5 is an enlarged sideeleva.

-tary view partly in section looking down upon the latch andcoil; Fig. 8is a front view of the mechanism shown in Fig. 6 looking toward the riht; Fig. v9 is a vertical sectional view, an Fig. 10 a rear elevation ofa still further embodiment of my inygntion; Figs. 11 and 12 arefragmentary views, in topplan and broken side elevation respectively, ofa floati armature embodiment of the invention; igs. 13 and 1-1 aresimilar views of a magnetically actuated counterbalance device providingfor overload and underlo'ad; and Fig. 15 is a fragmentary view, in sideelevation, and partly in section, of a-still further magneticcounterbalance movement.

Taking-the different constructions individually, it will be seen that inFig. 1 I have mounted on a suitable base 1 a usual heavy coil 2 securedby a binding post 3 and-connee-ted at its upper end to one terminal orcontact block 4:, the other block 5 connecting to a binding post 6. Saidcoil 2 is housed in a' shell 7, to which is pivoted at 8 an operatinghandle 9 whose lifting led es or flanges 10 .are in position to engagetie lower link. 11

of a toggle, the upper link 12 of which is' "the lower end of the fart19'. The operating handle 9 is provid with aiusualcatch 2-1 Thelatc'lr25 is carried by an armature 26 pivotedat 27 above the coil 2andf ovided with a rearward end 2-8 weigh or the armature,

otherwise counterbalanced, being shown in Fig. 1 as provided withweights 29. ,The

latch 25 is freely movable with relation to being herein shown asmounted'on the pivot 27 and is shown in Fig. 1 in the position normallyoccupied when engaged by the catch -24. The armature is provided with alip or cam surface 30 in osition to be engaged by the under side o thecatch 24 when t 'e latter is swung into closed position, whereby thearmature is automatically forced down against the end of the magnet core19. The latter is provided with brass pins 31 projecting slightly abovethe to surface so as to maintain an air gap an prevent the armature 26from clinging or being retained by the residual ma etism of the core. 7

Viewin ig. 2, it will be seen that the latch 25 1S narrow at its. rearportion and rests in a groove formed between the opposite sides of thearmature 26 and above the closed bottom 32 thereof, indicated by dottedlines in Fig. 1, so as to be freely movable vertically therein. Toinsure free movement at all times, dust and, the like are excluded by ahood or cap 33 preferably movable with the latch and inclosing bothlatch and armature. The engaging end of the latch 25 is mounted at sucha height that when the catch 24 engages therewith,

said latch will alwaysbe raised an appreciable distance above the bottomof the armature, as indicated in Fig. 1, where the dotted lower edge isshown in its normally engaged position with relation to the bottom 32 ofthe'armature. The purpose of this provision is .to insure a positive,hammer-like blow from the armature when the latter is released b ma eticfie d (upon the occurrence of an 'un e'rload condition).

' however, the current drops below normal,

-In Figs it is obvious that the armature willimmediately rise because ofthe counterbalance weights 29 and will give the latch 25 a sulficientblow to release the circuit breaker. If, on the other hand, an. overload should occur, the core 22 will be uickly raised. in the coil2thereby causingflits stem 21 forciblyuto engage the latch 25 andrelease the circuit ,breaker as before.

or lever 36. (apertured at 37 4 to receive the latch of the circuitbreaker) said link being a decrease of strength in the 'ne ted by alink6,7 to a bell crank 68 pivot ally mounted at 69 and provided at its free6-8 I have showna different embodiment for providin a strongermovearmature 47 which is likewise pivoted at 45 and is also pivotallyconnected. to a rearwardly extending counterbalance arm ,48 pivoted at49 and, provided with counterbalancin'g weights 50. r'

From the foregoing description it will be evident that when themagnetism of the core 19 decreases below normal, the armature 47 will bethereby released and will be forcibly raised into striking engagementagainst the end 49. of the latch so as to lower its engaging end 44 awayfrom the catch 35 and permit the circuit breaker to fly open; andlikewise when an overload takes place the plunger 21 of the lower coresimilarly strikes the latch for releasing the circuit breaker as before.

In Figs. 9 and 10 I have shown a construction similar to that shown inFig. 1, excepting that instead of having counterbalancing weights I haveprovided a deli cately vadjustable spring counterbalance,

shown as comprising a spring 51 secured to the outer end 52 of the arm28 and adjusted by means of a swiveled thumb-screw 53.

In Figs. 11 and 12 I have shown a latch 54 pivotally mounted in anarmature 55 pivoted at 56 and provided at its forward end and outersides with opposite counterbalaiicing .sprin 57 operating in op ositionto a movab e or'floating underloa ar-' mature 58 pivoted tothe mainarmature at 59'and normally attracted b a stationary iron .core 60against the in uence of said sprin s 57. A movable core 61 and its'stemor p unger- 62 cooperate with the above parts, said underload armature58.-being provided with an auxiliary opening 63 to permit the plunger 62to rise and strike against the latch 54 upon the occurrence of anoverload. v p

In Figs. 13 and 14 I have shown a form of magnetic release, comprisin alatch 64' and armature 65 the same as be ore, said armature having atail piece or counterbalancarm 66 extending rearwardly and conend withan enl-ar d armature portion .70 adjacent a magnetic extension 71 fromthe shell 7 (which in this case is composed of suitable'magnetizablematerial such as soft iron) In this case, .u onthe occurrence of anunderload'the bel crank armature will be permitted to fall away,thereby. forcibly raising the main armature into striking contact withthe latch 64. For overload, this construction is provided with a movablecore 7 2,the same as in Fi 1.

- In Fig. 15 I have shown a stlll further modification in which thelatch and its' armature are the same as in Fig. 14:, but said armatureis pivoted at 73 and has a counterbalancing arm 74 extending rearwardlyand downwardly and terminating in an armature-portion 75 opposite anextension 7 6 similar in construction and operation to the extension 71already described. A short, fixed core 77 is provided to cooperate withthe armature 65, being of such proportions that it will maintain 'saidarmature in engagement therewith when normal current is flowing. When adecrease of current occurs, the magnetism in the core 77 will beinsufiicient to hold the armature 65 which will then be raised by thecounterbalancing weight 74, 75 to release the latch 64:. Like- -wiseupon the occurrence of an overload the extension 76 will be magnetizedsufiiciently to draw the armature portion 75 of the counterbalancingdevice forcibly forward and release the latch 64. v

It will be understood that my invention is capable of a wide variety ofembodiments, some of the principal ones only having been described. Ineach case it will be seen that when the main armature has been releasedit is permitted to give a slight releasing blow to the latch. Also thepivotal arrangement of the latch allows the latter to separate from thearmature to admit the catch without tending to remove the armature fromits engagement with the magnet.

My principal aim has been to devise a construction whereby overload orunderload conditions will be providedfor by one operating means such asa single solenoid or coil.

templa-te employing various of the individual features in sub-combinations and in other connections, and, with that end in view, haveclaimed them as such hereinafter.

Having described my invention, what I claim as new and desire to secureby Letters Patent, is:

1. In an automatic circuit breaker, a single tripping coil, two separatecores for said coil, one being .movable and'the other statlons, anoperating handle Another aim has been to provide a delicate andsensltive construction, certaintionary and one being an underload coreand the other an overload core, a single armature besides said two coresmovable to ward and away from said cores and actuated b said coresrespectively in opposite direcrovided with a catch and a separatereleasing latch to engage said catch operated by said single ar matureto release said catch for opening the circuitbreaker.

'2. In an automatic circuit breaker, an operating handle provided with acatch, a latch to engage said catch for holding the circuit breakerclosed, an electro-magnetic controlling device, and a tripping armaturecontrolled thereby separate and distinct from said latch, having atitsfront end a projecting bottom portion-in the path of said handlecatch',the latter passing between said latch and bottom portion upon theclosing movement of the circuit breaker, for forcing said armature intooperative position.

3. In an automatic circuitbreaker, an operating handle providedw'ith acatch, an electro-magnetic controlling device, a trippingarmaturetherefor, and a latch operated by said armature and movablerelatively thereto, said armature and latch receiving between them, andbeing separated .by,said catch for retaining the circuit breaker closed.

4. In an automatic circuit-breaker, an electro-magnetic controllingdevice, a tripping armature therefor, a latch carried and operated bysaid armature and movable relativly thereto for locking thecircuitbreaker closed, and means constituting a part of the armatureoperated by the closing of the circuit breaker for forcing said armatureinto operative position. I

5. In an automatic circuit breaker, a looking catch for holding thecircuit breaker closed, an electro-magnetic controlling de- -1ng catchfor holding the circuit breaker closed, an electro-magnet-ic controllingdevice, a pivoted tripping armature therefor, a latch pivoted at itsrear end on the armature in position to engage at its forward end thecircuit breaker catch, said armature having at its forward end aproject-ing camshaped lip in line with said latch and normally separatedfrom the latter a less distance than the width of said catch, anextension projecting rearwardly from said ar- 4 esepos mature, andadjustable counterbalancing operating with said catch for crowding themeans therefor. armature-closeto said core when the circuit 7. In anautomatic circuit breaker, a sinbreaker is' closed. n I gle coil, a'shell inclosing the same, a sta- In testimony whereof I'have slgned my 5t ionary core fastened in said shell to the up name to thisspecification, in the-presence of '15 'per end thereof, an armatliremounted close two subscribing witnesses.

to'the upper end of said core, a latch pivoted v a on. said armature, acatch for engaging said Witnesses:

latch to retain the circuit breaker in closed Gno. HuMAXWELL, 10position, and means 'on said armature 00- M. A. Jones AUSTIN. E.GREENE."

